Electrical condenser



Mwah E5, 1932. W. M. BAlLEY ,849,862

ELECTRI CAL CONDENSER Filed Dec. 2l. 1927 FT #MVM-Tiff;

lhatented ar. l59 i932 WILLILEI M. BAILEY, OF LYNN, MSSACHUSETTS, ASSGNOR, BY iESNE ASSGNHENTS, TO GENE ELECTRIC COMPANY, A. CORPORATON OE' NEW YORK ELECTRCAL CONDENSER Application lled December 2, 1927. Serial No. 241,50?.

rlhis invention relates to electrical condensers of a type suitable Jfor use with coinparatively high powensuch as that employed'I in radio transmitting'circuits.

A. feature ot the invention is a condenser for use 1n comparatively high power circuits -and provided with a shield for distributing casing for the condenser and novel nieans for securing the cover thereto. rlhe casing includes a long surface creepage path between parte oi opposite polarity and is shielded trom rain.

The invention also consists in certain new and original features of construction and combinations of parts hereinafter set forth and claimed.

Although the novel 'features which are believed to be characteristic ci this invention will be particularly pointed out in the claims appended hereto, the invention itself, as to its objects and advantages, the mode of its operation and the manner ci its organization may be better .understood by referring to the following description taken in connection with the accompanying drawings forming a part thereof, in which Fig'. l is a vertical section or" the condenser taken on the line 1 1 of Fig. 2 and looking in the direction oia the arrows;

Fig. 2 is a bottom pla-n view oit the con denser with the cover partly broken 'away showing the interior arrangement of the parts; and

Fig. 3 is an elevation partly in section of a modified Jform oi condenser provided with contactfeet to facilitate series connections.

-Like reference characters denote like parts inthe several figures of the drawings.

lin the following description and in the claims parts will be identiied b v specific names for convenience, but they are intended to be as generic in their application to similar parts as the art will permit.

Referring to the drawings more in detail, the invention is shown as applied to a condenser staclr S enclosed in a suitable casing which serves asa support for the condenser itself and for the terminal members thereof.

rEhe casing comprises an insulating cup member D which may be Jiormed of molded vitreous material such as isolantite or other suitable insulating material. Secured to said casing l) is a base cover element BE provided with an upwardly extending flange AB surrounding the adjacent portion of the casing l) and spaced therefrom. portions of flange AB and the insulating casing may be provided with grooves Til/l and Tl respectively for cooperating with cement C or other suitable filling material. for holding' and rigidly securing the elements together. The base element BE is provided with an interior opening across which pressure bar PB is secured. rl`he ends of said har rest on portions of the hase element on opposite sides of said opening and are frictionally held in contact therewith when the stack is assembled.

lressure screw PS is threaded in pressure bar PB and is utilized for exerting pressure upon pressure plate l?? and clamping the condenser stack S between said plate and the bottom of casing D. Stack S may comprise a pluralityol3 units formed of conducting foils and dielectric material in the'usual manner and oined together in series relationship as by connection SC. rlhe particular construction oi the condenser stack, however, forms no partei the present invention.

Contact plate CP is positioned between the bottom of insulating cup D and stack S in electrical contact with contact strip CS-l which may he electrically connected to the outer foil oi condenser stack S as by connection EC. Terminal stud TS is secured to contact plate CP and extends through a suitable aperture in casing D forming one terminal ot the condenser. Connecting strips CS-Q and CS-3 connect the opposite terminal of condenser stack S to base element BE, said strips being passed around flange rlhe adjacent f rea dit

AS of said element and secured thereto as by screws SR.

After the condenser has been 'securely clamped in place, the space between the condenser staelr. S- and casing D may be lilled with suitable insulating illing -material F. ,A metal cover MC may then be secured, as by screws SR, to base element BE for protecting pressure screws PS and preventing accidental turning thereof.

Shield TE may be carried by terminal stud TS and separated from the bottom of casing D as by dexible spacing element LS which may be formed of lead -or other suitable material. Shield TE may be secured to member D as by nuts LN and BN threaded upon Iterminal stud TS cooperating with washer W. Said member TE is preferably cupped, the sides N S extending concentric with and parallel to the cylindrical sides of member D ut spaced therefrom.

Member TE, being electrically connected to terminal stud TS, serves to distribute the electrostatic stress and to prevent a corona discharge or breakdown. The shield also operates as a heat radiating member and assists in cooling said terminal stud as Well as a rain shield for preventing moisture from forming on cup D. ln order to avoid damage due to an excess voltage, a spark gap may be provided as by inserting an electrode E in a suitably tapped hole in member TE .and securing the same as by set screw SS.

Electrode E is in suitable position to coopcrate with ange AB of base element BE and form a spark gap which may be adjusted. to break down at any given voltage.

In the modification shown in Fig. 3, the condenser is constructed as above described with the exception of feet FT which are formed on both the base element and the shield. lin this case the terminal stud TS is threaded into the shield TE and rigidly secured thereby, the shield itself serving as a terminal for the condenser. The condensers are thus adapted to be arranged in stacked formation in case a plurality of units are to v be connected inA series. I

The type of casing above descr1bed provides a long surface distance between oppo site terminals and reduces the surface creepage. TheI rain shield assists in reducing the creepage by insuring a dry surface. The losses are reduced due to the length of dielectric between parts of opposite polarity and the use of only a single cemented ring for closing the casing.

The casing has been described as formed l or isolantite, a vitreous material moulded in a plastic state and red. It is, however, not limited to this materialbut may comprise glass, porcelain, phenol condensation product or ot The provision of feet to facihtate stacking and series connection is especially ader strong insulating substances.

vantageous in applying the condenser to commercial conditions. The mechanical support also serves as an electrical connection and reduces the parts required.

While certain novel features of the inven-` tails of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. l

What is claimed is:

l. A. stack condenser, an insulating casing therefor', a base element forming a closure for said casing, means for clamping said stack under pressure, contact strips connecting one terminal of said stack with said base element, a terminal element extending through said casing and forming the other terminal of said stack, means for distributing the electrostatic stress thereabout comprising a metallic cupped shield spaced from said casing and an electrode carried by said shield and forming in connection with said base element a safety spark gap.`v

2. ln combination with a condenser stack, an insulating casing having an open end, a closure member for said end, means for ce- -menting said member to said casing, said having an open end and a closed end, a contact plate electrically connected to one terminal of said stack Aand interposed between said stack and closed end of said casing, a terminal stud secured to said contact plateand extending through said end, a metallic ,cover member, means for securing said member tothe open end of said casing and means carried against said contact plate.

4f. The combination with an electrical condenser, of a casing of insulating material enclosing said condenser on the sides and one end, a terminal projecting thru said casing at the end of the condenser enclosed by said casing and rigid metallic means spaced from and substantially parallel to the sides and end wall of said casing for mechanically protecting the closed end of said casing.

5. The combination with an electrical condenser, of a casing of insulating material enclosing said condenser on the sides and one end, a terminal projecting thru said casing at'the end of the condenser enclosed by said casing and'rigid metallic end member connected to said terminal and extending across Htl by said member for clamping'said stack lic :Massa the insulating end wall of said casing and around the casing side walls to remove mechanica'l and electrical stresses from casing endwallu 6. An electric condenser comprising. a stack of dielectric and armature elements, a casing of structural insulating material having one end closed by the insulating material of said casing to an amount suiiicient to require insertion of said stack through the 0pposite end of the casing, said opposite end of the casing being bridged by a metal member secured thereto, said stack being clamped b6- tWeen said metal member and the closed end of the casing, the end closing portion of the insulating casing transmitting stack clamping stress7 a terminal extending out through the closed end of the casing and an opposite stack terminal being connected to said metal member.

7. An electric condenser comprising a stack of dielectric and armature elements, a casing of structural insulating material having one end closed by the insulating material of said casing to an amount suiiicient to requirel insertion of said stack through the o posite end of the casing, said opposite end o the casing being brid ed by a metal member` secured thereto, said stack being clamped vbetween said metal member and the closed end of the casing7 the end closing portion of the insulating .casing transmitting stack clamping stress, a terminal extending out through the closed end of the casing and an opposite stack terminal being connected to said metal member, said metal end member being perforate for insertion of said, stack, and means bridging the perfor-ate portion of said metal member and transmitting stack clamping stress.

8. An electric condenser comprising astack of dielectric and armature elements, a casing of structural insulating material having one end closed by the insulating material of said casing to an amount sucient to require insertion of said stack through the opposite end of the casing, said opposite end of the casing being bridged by a metal member secured thereto, said stack being clamped between said metal member and the closed end of the casi11g,the end closing portion of the insulating casing transmitting stack clamping stress, a terminal extending out through the closed end of the casing and an opposite stack terminal being connected to said metal member, and means for adjusting stack clamping compression on said stack through at least one end of the casing.`

ln testimony wher-coi' l hereunto ax my signature.

lVLLiili/ lli. lilLEY. 

